小麦亲本及其杂交后代苗期氮代谢相关指标的遗传与表达差异  

Research on Heredity and Gene Expression Differences for Nitrogen Metabolism-Related Indices of Wheat Parents and Their Hybrids at Seedling Stage

作　　者：王琳琳[1] 王平[1,2] 王振林[1] 孙爱清[1] 杨敏[1] 王春微[1] 仪小梅 韩晓玉[1] 尹燕枰[1] 

机构地区：[1]山东农业大学农学院/作物生物学国家重点实验室/山东省作物生物学重点实验室,山东泰安271018 [2]泰安市农业科学研究院,山东泰安271000

出　　处：《中国农业科学》2014年第12期2300-2312,共13页Scientia Agricultura Sinica

基　　金：国家公益性行业(农业)科研专项(201203029)

摘　　要：【目的】分析小麦氮代谢相关指标的遗传与表达差异,为选育小麦氮高效品种提供理论依据。【方法】选用6个不同氮效率小麦品种及其组配的3个杂交组合,采用霍格兰营养液进行苗期试验,设置3个氮水平:低氮(LN)、正常供氮(CK)、高氮(HN),分别为0.2、4和8 mmol·L-1,在3个氮水平下对小麦苗期形态、氮代谢相关酶、氮含量和氮素积累量进行遗传分析,同时探讨了根叶的氮代谢相关基因的表达量差异。【结果】根长和根鲜重在低氮水平下明显高于正常供氮,杂种优势表现为负向。苗高和苗鲜重随着氮水平的增加呈抛物线增长趋势,杂种优势表现为超中亲甚至超高亲。根长随氮水平增加先大幅降低后趋于平缓,而苗高则先大幅下降后趋于平缓。根苗鲜重变化规律与根长和苗高一致。根含氮量随着氮水平增加呈上升趋势,而叶片含氮量和氮素积累量则先大幅升高后小幅下降,高氮水平下根叶含氮量杂种优势显著。硝酸还原酶活性和谷氨酰胺合成酶活性均随着氮水平升高而升高,硝酸还原酶活性的杂种优势均为负向,而谷氨酰胺合成酶活性表现为正向杂种优势。硝酸还原酶活性的杂种优势变化与根系性状基本一致,谷氨酰胺合成酶活性杂种优势与地上部幼苗性状基本一致。根系硝酸转运蛋白的3个基因的表达量趋势一致,均随着氮水平升高呈先大幅下降后趋于平缓,且杂种优势整体表现为正向。叶片NRT1.1和GS1c的表达量均随着氮水平增加呈先大幅上升后小幅下降趋势,杂种优势整体表现为正向。小麦根系与叶片NRT1.1的表达变化趋势不一致,根系NRT1.1的表达量在氮胁迫时大幅升高,而叶片NRT1.1的表达量在氮胁迫时大幅下降。综合所测15项指标结果显示,在低氮水平下低氮高效品种YM35和高氮水平下高氮高效品种DK138多数指标较高。组合YM35×DK138是由低氮高效品种和高氮高效�【Objective】This study aims to analyze the heredity and gene expression differences of wheat nitrogen metabolismrelated indices, which will provide a theoretical basis for selecting wheat cultivars of high nitrogen utilization.【Method】Six wheat varieties with different nitrogen use efficiency and their three hybrid progenies were used as materials which were grown in Hoagland＇s nutrient solution with 3 nitrate levels at seedling stage, that are low nitrogen（LN）, normal nitrogen（CK） and high nitrogen（HN） at 0.2, 4 and 8 mmol·L-1, respectively. Heredity of morphology, nitrogen metabolism-related enzymes, nitrogen content and nitrogen accumulation in wheat seedling stage and gene expression differences of root and leaf under three nitrogen levels were explored. 【Result】Root length and fresh weight under low nitrogen level were significantly higher than those under normal nitrogen level and their negative heterosis was observed. Seedling height and fresh weight indicating mid-parent heterosis and even super-parent heterosis showed a parabolic trend with the nitrogen level increasing. Root length declined quickly originally and then leveled off with increasing level of nitrogen, while seedling height increased quickly at first and then trended to be stable with the rate of nitrogen increasing. The variation of fresh weight in root and seedling were consistent with root length and seedling height. Nitrogen content of root increased, while that of leaf increased initially and then declined slightly with the rising nitrogen level, nitrogen accumulation as well. Heterosis of nitrogen content in root and leaf was significant under the high nitrogen level. The activity of nitrate reductase and glutamine synthetase was increased with increasing level of nitrogen. Heterosis of nitrate reductase activity was negative, while that of glutamine synthetase activity was positive. Heteroses of nitrate reductase activity and root traits were basically identical, while that of glutamine synthetase activity an

关 键 词：小麦 氮代谢 杂种优势 基因表达 遗传 

分 类 号：S512.1[农业科学—作物学]